1. Field of Invention
The invention relates to an inking system of a printing press having an impression cylinder for guiding a printing substrate, at least one ink-transfer roller comprising a cylinder mandrel, on which at least one cylinder sleeve is concentrically displaceable, and bearing blocks, in which ends of the ink-transfer roller are mounted and which are displaceable independently of each other relative to the impression cylinder so that the ink-transfer roller can be set against the impression cylinder or any other ink-transfer roller, with a bearing block being detachable from one end of the ink-transfer roller and displaceable relative to the ink-transfer roller so that the at least one cylinder sleeve can be removed by way of the aforementioned one end. The invention also relates to a method of sliding a cylinder sleeve onto an ink-transfer roller that employs the elements of the above-described system.
2. Description of the Prior Art
It is frequently necessary to change ink-transfer rollers of one or more inking systems for carrying out print jobs. The document DE 102 20 608 C1 describes this process in detail, for example. The process in question relates primarily to print rollers that carry the print motif while other ink-transfer rollers, for example, anilox rollers, can frequently remain in the printing press. An inking system serves to print a motif by the use of a single ink. In different printing presses, an impression cylinder guiding the printing substrate can be assigned to each inking system. In other printing presses, it is possible to arrange a plurality of inking systems around a single impression cylinder. In this case, the printing substrate that is then usually present in the form of a web need not leave the impression cylinder, which is of advantage when printing plastic webs, for example. Such printing presses are often referred to as central cylinder printing presses and are primarily used in the field of package printing. The preferred printing process for this purpose is flexographic printing.
In order to simplify and thus accelerate the process of setting up the printing press for the next job, the ink-transfer rollers are often provided with a multipart construction. A first part is the cylinder mandrel that remains in the printing press. One or more cylinder sleeves can now be slid onto this cylinder mandrel, the outer sleeve carrying a functional element. That is to say, the printing-cylinder sleeve carries the printing plate. All the inner sleeves serve only for adapting the diameter of the roller and thus the printing length and are therefore referred to as adapter sleeves. The inner sleeves are often limited to one sleeve at most for reasons of stability.
For changing the cylinder sleeves, the cylinder mandrel that is otherwise mounted at both ends thereof in bearing blocks that are displaceable relative to the frame of the printing press or the impression cylinder is exposed at one end thereof. For this purpose, the cylinder mandrel is detached from the bearing block in question. This bearing block is then displaced relative to the cylinder mandrel so that one or more sleeves can now be pulled off by way of this free end in the axial direction of the ink-transfer roller and new sleeves can be slid onto the same.
For defining the axial position of a sleeve on the cylinder mandrel, the latter often comprises a stationary ring, against which the cylinder sleeve is slid. In doing so, the cylinder sleeve often violently strikes against the ring so that this results in damage to cylinder sleeves or cylinder mandrels in the long term, more particularly when the cylinder sleeves are adapter sleeves that are heavy, in part.